Because of public concern over injuries and deaths to children caused by physically harmful materials, such as medicine, cleaning solutions and other products found in homes, the United States government has enacted regulations covering the performance criteria for safety closures for such products. These performance criteria comprise testing procedures which include attempts by representative samples of children and adults to open containers with safety closures on them within a given period of time. While it is important to reduce the percentage of children who can open such safety closures or child resistant closures, it is equally important to enable adults to be able to open the closure easily and effectively after reading accompanying instructions.
One class of products for which child resistant safety closures are required is food supplements and vitamins. While these products are not inherently harmful, overdoses of many vitamins and food supplement products can be quite harmful, particularly to children. Consequently, it is necessary, in the United States, to package many food supplement products with child resistant closures. A number of different safety closure designs have been developed, both of a snap cap and a screw cap type; but many of these closures fail to meet the stringent federal safety regulations. Such failures particularly take place when prying or biting of the cap is employed by the child or person attempting to open or remove the closure.
A closure designed to provide the desired degree of child resistant safety, which also is reclosable after opening, and which is capable of repeated opening and closing cycles, is disclosed in the patent to Towns U.S. Pat. No. 3,845,872. This patent discloses a press-down lift-up closure of the type suitable for use on vitamin containers or the like. The closure comprises a snap-fitted plug, which fits into the top of the container in such a way that there are no slots into which teeth or fingernails can extend. The top of the plug has a hollow recess formed beneath a lift tab, which is placed in the top. The lift tab is hinged at one edge and snaps into place in a groove along the other edge to hold it in place over a fulcrum extending across the closed bottom of the recess. To permit opening of the closure, the tab on the top is pressed down between the hinge and the fulcrum to pop open the opposite edge and lift it clear of the top. This opposite edge then may be grasped and used to pull the entire cap off the bottle.
The lift tab opening of the type which is disclosed in the Towns U.S. Pat. No. 3,845,872 also is used on containers for charcoal lighter and the like, where the lift tab also includes a small projection extending into and sealing a small opening in the top of a bottle when the lift tab is closed. When it is lifted out of place, the plug or projection on the underside of the lift tab is removed from the small opening in the top; so that fluid may be removed from the bottle. The opening in such a safety closure cap typically is quite small, to permit a small stream of fluid to be poured from the container closed by the cap. Closures of this type are resealable by pressing the free or unhinged edge of the lid back in place. Such closures have found widespread use.
Another tab mechanism, similar to that disclosed in the Towns U.S. Pat. No. 3,845,872, includes a base closure which is secured to the top of the container in a non-removable fashion after the container has been filled with product, such as vitamins or the like. An insert then snaps into the interior of the base closure. When the insert is snap pressed into place, it cannot easily be pried up from around the edge, since there is no lip under which a fingernail or other tool may be inserted. To permit removal of the insert, a lift tab is placed in the center of the insert. There is a hollow space provided in the insert, beneath the lift tab, and a fulcrum mechanism similar to that described above in conjunction with the Towns patent is employed. When a dot on the tab is pressed, a fulcrum causes the opposite end of the lift tab to pop upwardly. The free end then is grasped; and the entire insert is lifted out of the base closure. This exposes an opening in the container, since the insert is fully removed from the base closure. A problem which exists with an insert of this type is that it can be misplaced or lost, leaving the container open.
Another patent which is directed to a closure for a pill or vitamin container is the U.S. patent to Laauwe U.S. Pat. No. 4,262,802. This closure includes a main cap portion, which is permanently sealed to or attached to the top of the container. A "push-down, pull-up" top or cover then is placed over an opening in the main cap portion. This cover is hinged and extends across a relatively small opening in the top of the closure opposite the hinged end of the cover. Adjacent the hinged end, the top of the cover on the container includes a closed recess with a fulcrum across it; so that when the closure tab is in its closed position, it engages the fulcrum located at one edge of the recess formed in the cap. The tab is opened in a manner similar to that described above for the Towns patent; and it then can be lifted and pivoted away from the opening on the hinge to permit the contents of the container to be poured out through the opening. Because of the nature of the construction of the closure, only a limited opening in the top of the container is available. The construction of the fulcrum and the closed recessed area for applying pressure to open the tab extends over a major portion of the top of the container.
Other United States patents, such as those to Ostrem U.S. Pat. No. 3,894,653; LaCroce U.S. Pat. No. 3,929,252; Hasegawa U.S. Pat. No. 3,957,172; Kowalik et al. U.S. Pat. No. 3,958,718; Hasegawa U.S. Pat. No. 4,165,017; and Hannon U.S. Pat. No. 5,007,554 are directed to non-reclosable lift top tab mechanisms for beverage containers. While these lift top tab closures are child resistant, they are not reclosable or reusable for repeated opening and closing cycles. Consequently, the mechanisms of these patents are not appropriate for use in conjunction with pill containers or vitamin containers and the like.
It is desirable to provide a tablet dispensing closure for containers, particularly pill containers or vitamin containers, which overcomes the disadvantages of the prior art and which provides convenient dispensing of the contents of the container, without removing the closure or any part of it from the top of the container once it has been put into place.